U.S. Pat. No. 6,947,732 generally relates to a method of accessing a mobile vehicle using a wireless communication system. A vehicle communication device is placed into a first communication service sleep mode of a sleep cycle. It is determined if a first communication service is currently available to the vehicle communication device. If the first communication service is available, the vehicle communication device remains in a first communication service awake mode for a first interval of the sleep cycle. If the first communication service is not available, the vehicle communication device remains in the first communication service sleep mode for the first interval of the sleep cycle. Programs and systems of using the method are also provided.
U.S. Pat. No. 8,000,842 generally relates to a system and method that prevent excessive current drain through the network access device (NAD) of a telematics unit and provide flexible discontinuous-receive management. Normally, when in a Standby State and where communication service is unavailable, the NAD may dissipate current at rate many times more than where communication service is available. A Standby Counter provides the length of the time interval for Standby State or the sleep cycle. Certain of the disclosed examples prevent excessive vehicle battery drain by operating the telematics unit in a first mode wherein a sleep cycle value of the telematics unit is above a first predetermined threshold, and if the communication service is available, operating the telematics unit in a second mode wherein a sleep cycle value is in a range from zero to the first predetermined threshold.
U.S. Pat. No. 8,005,453 generally discloses a system and method in a client device for controlling the power within the client device. The client device has a network access device, a programmable timer, and a controller. The network access device has at least a powered state and a power-off state. The programmable timer operates the network access device in the powered state. The controller is coupled to the programmable timer and is capable of providing a time period for operating the network access in the powered state. The controller determines the time period based on a discontinuous reception parameter obtained from the network access device. The network access device may include a transceiver. The network access device may also include a transceiver and a controller. There are also methods of operating the client device to control the power within the device.